/**
* graphene_euler_to_vec3:
* @e: a #graphene_euler_t
* @res: (out caller-allocates): return location for a #graphene_vec3_t
*
* Retrieves the angles of a #graphene_euler_t and initializes a
* #graphene_vec3_t with them.
*
* Since: 1.2
*/
void
graphene_euler_to_vec3 (const graphene_euler_t *e,
graphene_vec3_t *res)
{
graphene_vec3_init_from_vec3 (res, &e->angles);
graphene_vec3_scale (res, (180.f / GRAPHENE_PI), res);
}
/**
* graphene_ray_get_distance_to_point:
* @r: a #graphene_ray_t
* @p: a #graphene_point3d_t
*
* Computes the distance from the origin of the given ray to the given point.
*
* Returns: the distance of the point
*
* Since: 1.4
*/
float
graphene_ray_get_distance_to_point (const graphene_ray_t *r,
const graphene_point3d_t *p)
{
graphene_vec3_t point;
graphene_vec3_t tmp;
float distance;
graphene_point3d_to_vec3 (p, &point);
graphene_vec3_subtract (&point, &r->origin, &tmp);
distance = graphene_vec3_dot (&tmp, &r->direction);
/* the point is behind the ray */
if (distance < 0)
{
graphene_vec3_subtract (&r->origin, &point, &tmp);
return graphene_vec3_length (&tmp);
}
/* get the position on the ray at the given distance */
graphene_vec3_scale (&r->direction, distance, &tmp);
graphene_vec3_add (&tmp, &r->origin, &tmp);
graphene_vec3_subtract (&tmp, &point, &tmp);
return graphene_vec3_length (&tmp);
}
/**
* graphene_triangle_get_midpoint:
* @t: a #graphene_triangle_t
* @res: (out caller-allocates): return location for the coordinates of
* the midpoint
*
* Computes the coordinates of the midpoint of the given #graphene_triangle_t.
*
* Since: 1.2
*/
void
graphene_triangle_get_midpoint (const graphene_triangle_t *t,
graphene_point3d_t *res)
{
graphene_vec3_t tmp;
graphene_vec3_add (&t->a, &t->b, &tmp);
graphene_vec3_add (&tmp, &t->c, &tmp);
graphene_vec3_scale (&tmp, (1.f / 3.f), &tmp);
graphene_point3d_init_from_vec3 (res, &tmp);
}
/**
* graphene_ray_get_position_at:
* @r: a #graphene_ray_t
* @t: the distance along the ray
* @position: (out caller-allocates): return location for the position
*
* Retrieves the coordinates of a point at the distance @t along the
* given #graphene_ray_t.
*
* Since: 1.4
*/
void
graphene_ray_get_position_at (const graphene_ray_t *r,
float t,
graphene_point3d_t *position)
{
graphene_vec3_t res;
graphene_vec3_scale (&r->direction, t, &res);
graphene_vec3_add (&res, &r->origin, &res);
graphene_point3d_init_from_vec3 (position, &res);
}
/**
* graphene_euler_init_from_vec3:
* @e: the #graphene_euler_t to initialize
* @v: (nullable): a #graphene_vec3_t containing the rotation
* angles in degrees
* @order: the order used to apply the rotations
*
* Initializes a #graphene_euler_t using the angles contained in a
* #graphene_vec3_t.
*
* If the #graphene_vec3_t @v is %NULL, the #graphene_euler_t will be
* initialized with all angles set to 0.
*
* Returns: (transfer none): the initialized #graphene_euler_t
*
* Since: 1.2
*/
graphene_euler_t *
graphene_euler_init_from_vec3 (graphene_euler_t *e,
const graphene_vec3_t *v,
graphene_euler_order_t order)
{
if (v != NULL)
graphene_vec3_scale (v, (GRAPHENE_PI / 180.f), &e->angles);
else
graphene_vec3_init_from_vec3 (&e->angles, graphene_vec3_zero ());
e->order = order;
return e;
}
/**
* graphene_triangle_get_normal:
* @t: a #graphene_triangle_t
* @res: (out caller-allocates): return location for the normal vector
*
* Computes the normal vector of the given #graphene_triangle_t.
*
* Since: 1.2
*/
void
graphene_triangle_get_normal (const graphene_triangle_t *t,
graphene_vec3_t *res)
{
graphene_vec3_t v1, v2, tmp;
float length_sq;
graphene_vec3_subtract (&t->c, &t->b, &v1);
graphene_vec3_subtract (&t->a, &t->b, &v2);
graphene_vec3_cross (&v1, &v2, &tmp);
length_sq = graphene_vec3_dot (&tmp, &tmp);
if (length_sq > 0)
graphene_vec3_scale (&tmp, 1.f / sqrtf (length_sq), res);
else
graphene_vec3_init_from_vec3 (res, graphene_vec3_zero ());
}
/**
* graphene_ray_get_closest_point_to_point:
* @r: a #graphene_ray_t
* @p: a #graphene_point3d_t
* @res: (out caller-allocates): return location for the closest point3d
*
* Computes the point on the given #graphene_ray_t that is closest to the
* given point @p.
*
* Since: 1.4
*/
void
graphene_ray_get_closest_point_to_point (const graphene_ray_t *r,
const graphene_point3d_t *p,
graphene_point3d_t *res)
{
graphene_vec3_t point, result;
float distance;
graphene_point3d_to_vec3 (p, &point);
graphene_vec3_subtract (&point, &r->origin, &result);
distance = graphene_vec3_dot (&result, &r->direction);
if (distance < 0)
graphene_vec3_init_from_vec3 (&result, &r->origin);
else
{
graphene_vec3_scale (&r->direction, distance, &result);
graphene_vec3_add (&result, &r->origin, &result);
}
graphene_point3d_init_from_vec3 (res, &result);
}
